Finding the Fourth Proportional to 1,585,386, 2,378,326.59 and 520,185.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,585,386 : 2,378,326.59 = 520,185.78 : x
2. Step 2: Convert to fraction form
   1,585,386/2,378,326.59 = 520,185.78/x
3. Step 3: Cross multiply
   1,585,386x = 2,378,326.59 × 520,185.78
4. Step 4: Simplify right side
   1,585,386x = 1,237,171,672,313.89
5. Step 5: Solve for x
   x = 1,237,171,672,313.89/1,585,386
6. Step 6: Final answer
   x = 780,359.91